/* ============================================================================
   Weifeng Ye · yei1y.github.io
   "Paper & Data" v3 — a quiet academic reading surface where colour is reserved
   for data. One accent (mint) runs the interface; the six macaron hues appear
   only where they encode something: a bar, a coefficient, a funnel step.
   ----------------------------------------------------------------------------
   01 Tokens            07 Project entries + evidence figures
   02 Reset & base      08 Honors
   03 Layout            09 Contact / footer
   04 Navigation        10 Projects page (tables & cards)
   05 Hero              11 Motion · responsive · print
   06 About / Skills
   ========================================================================= */

/* ---------------------------------------------------------------- 01 Tokens */
:root {
  /* --- Data hues: a tint for washes, a deep tone for text and for bars ---
     Used ONLY by evidence figures and by the few places that label data.   */
  --tint-mint:   #DCF4EA;
  --tint-sky:    #DFEEFB;
  --tint-lav:    #E7E0F8;
  --tint-pink:   #FBE1EA;
  --tint-peach:  #FDE7DA;
  --tint-lemon:  #FAF0CB;

  --deep-mint:   #1F7A66;
  --deep-sky:    #2A6797;
  --deep-lav:    #61479B;
  --deep-pink:   #A84762;
  --deep-peach:  #9C552E;
  --deep-lemon:  #7E6410;

  /* --- The single interface accent --- */
  --acc:      var(--deep-mint);
  --acc-tint: var(--tint-mint);

  /* --- Paper & ink --- */
  --paper:     #FBFAF6;
  --paper-2:   #F4F2EC;
  --surface:   #FFFFFF;
  --ink:       #1B252B;
  --ink-2:     #4A585F;
  --ink-3:     #5F6C74;   /* third level still clears WCAG AA on all paper tones */
  --rule:      #E4E1D9;
  --rule-2:    #EFEDE6;

  --shadow-1: 0 1px 2px rgba(27, 37, 43, .04);
  --shadow-2: 0 1px 2px rgba(27, 37, 43, .04), 0 8px 24px rgba(27, 37, 43, .06);
  --shadow-3: 0 2px 6px rgba(27, 37, 43, .05), 0 20px 48px rgba(27, 37, 43, .09);

  /* --- Type --- */
  --serif: 'Source Han Serif SC', 'Noto Serif SC', 'Songti SC', 'STSong', 'SimSun',
           'Iowan Old Style', 'Palatino Linotype', Palatino, Georgia,
           'Times New Roman', serif;
  --sans:  -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC',
           'Hiragino Sans GB', 'Microsoft YaHei', 'Noto Sans SC', Roboto,
           Helvetica, Arial, sans-serif;
  --mono:  ui-monospace, SFMono-Regular, 'SF Mono', Menlo, Consolas,
           'Liberation Mono', monospace;
  --num:   'Iowan Old Style', 'Palatino Linotype', Palatino, Georgia,
           'Times New Roman', 'Songti SC', serif;

  /* --- Geometry --- */
  --wrap:     1120px;
  --wrap-txt: 760px;
  --nav-h:    64px;
  --r-lg:     16px;
  --r-md:     11px;
  --r-sm:     7px;
  --ease:     cubic-bezier(.22, .61, .36, 1);
  --t:        .3s var(--ease);

  color-scheme: light;
}

[data-theme="dark"] {
  --tint-mint:   #17322C;
  --tint-sky:    #172C3D;
  --tint-lav:    #262244;
  --tint-pink:   #37202A;
  --tint-peach:  #35251C;
  --tint-lemon:  #322C15;

  --deep-mint:   #79D6BC;
  --deep-sky:    #8CC2EE;
  --deep-lav:    #B7A3EA;
  --deep-pink:   #F0A0BB;
  --deep-peach:  #EEAC85;
  --deep-lemon:  #E0C465;

  --paper:     #12181D;
  --paper-2:   #171E24;
  --surface:   #1A2229;
  --ink:       #E8EEF2;
  --ink-2:     #A6B4BD;
  --ink-3:     #8A98A1;
  --rule:      #2A343D;
  --rule-2:    #212A32;

  --shadow-1: 0 1px 2px rgba(0, 0, 0, .3);
  --shadow-2: 0 1px 2px rgba(0, 0, 0, .3), 0 8px 24px rgba(0, 0, 0, .3);
  --shadow-3: 0 2px 6px rgba(0, 0, 0, .34), 0 20px 48px rgba(0, 0, 0, .42);

  color-scheme: dark;
}

/* Data-hue switch: set on a figure, a card or a row to recolour its marks */
[data-accent="mint"]  { --acc: var(--deep-mint);  --acc-tint: var(--tint-mint); }
[data-accent="sky"]   { --acc: var(--deep-sky);   --acc-tint: var(--tint-sky); }
[data-accent="lav"]   { --acc: var(--deep-lav);   --acc-tint: var(--tint-lav); }
[data-accent="pink"]  { --acc: var(--deep-pink);  --acc-tint: var(--tint-pink); }
[data-accent="peach"] { --acc: var(--deep-peach); --acc-tint: var(--tint-peach); }
[data-accent="lemon"] { --acc: var(--deep-lemon); --acc-tint: var(--tint-lemon); }

/* -------------------------------------------------------- 02 Reset & base */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 24px);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.78;
  color: var(--ink);
  background: var(--paper);
  letter-spacing: .004em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  transition: background var(--t), color var(--t);
}

a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; height: auto; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
ul, ol { list-style: none; }
table { border-collapse: collapse; width: 100%; }
strong, b { font-weight: 650; color: var(--ink); }
sup, sub { font-size: .74em; line-height: 0; }
code, .mono {
  font-family: var(--mono);
  font-size: .87em;
  padding: .1em .38em;
  border-radius: var(--r-sm);
  background: var(--paper-2);
  color: var(--ink-2);
  border: 1px solid var(--rule-2);
}

::selection { background: var(--tint-lemon); color: #43350A; }
[data-theme="dark"] ::selection { background: #4A3F14; color: #FBF3D2; }

:focus-visible {
  outline: 2px solid var(--deep-sky);
  outline-offset: 3px;
  border-radius: 4px;
}

/* Bilingual switch: `html[data-lang]` drives which span is visible */
html[data-lang="zh"] .en { display: none !important; }
html[data-lang="en"] .zh { display: none !important; }

/* Inline pairs must not break the line box */
span.zh, span.en { display: inline; }

/* ------------------------------------------------------------- 03 Layout */
.wrap { width: 100%; max-width: var(--wrap); margin-inline: auto; padding-inline: 28px; }
.wrap--txt { max-width: var(--wrap-txt); }

.section { padding: 86px 0; position: relative; }
.section--band {
  background: var(--paper-2);
  border-block: 1px solid var(--rule-2);
}

/* Section heading: a numbered, paper-like label with a hairline */
.head { margin-bottom: 40px; }
.head-label {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 14px;
}
.head-label::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--rule);
}
.head-label b { color: var(--acc); font-weight: 600; }

.head h2 {
  font-family: var(--serif);
  font-size: clamp(26px, 3.4vw, 37px);
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -.01em;
}
.head h2 + p {
  margin-top: 16px;
  max-width: 720px;
  color: var(--ink-2);
  font-size: 15.5px;
}
.head h2 + p a { color: var(--ink); border-bottom: 1px solid var(--rule); }
.head h2 + p a:hover { border-bottom-color: var(--acc); color: var(--acc); }
.head--center { text-align: center; }
.head--center .head-label { justify-content: center; }
.head--center .head-label::after { max-width: 80px; }
.head--center h2 + p { margin-inline: auto; }

/* Prose — serif body for the "read like a paper" sections */
.prose { font-family: var(--serif); font-size: 17px; line-height: 1.95; color: var(--ink-2); }
.prose p + p { margin-top: 1.15em; }
.prose strong { color: var(--ink); font-weight: 600; }
.hl { padding: .06em .3em; border-radius: var(--r-sm); box-decoration-break: clone; -webkit-box-decoration-break: clone; }
.hl--mint  { background: var(--tint-mint);  color: var(--deep-mint); }
.hl--sky   { background: var(--tint-sky);   color: var(--deep-sky); }
.hl--lav   { background: var(--tint-lav);   color: var(--deep-lav); }
.hl--pink  { background: var(--tint-pink);  color: var(--deep-pink); }
.hl--peach { background: var(--tint-peach); color: var(--deep-peach); }
.hl--lemon { background: var(--tint-lemon); color: var(--deep-lemon); }

/* Reading progress hairline — one accent, not a rainbow */
.progress {
  position: fixed;
  inset: 0 auto auto 0;
  height: 2px;
  width: 0;
  z-index: 120;
  background: var(--deep-mint);
  transition: width .12s linear;
}

/* --------------------------------------------------------- 04 Navigation */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-h);
  background: var(--paper);
  background: color-mix(in srgb, var(--paper) 84%, transparent);
  backdrop-filter: saturate(160%) blur(14px);
  -webkit-backdrop-filter: saturate(160%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--t), background var(--t);
}
.nav.is-stuck { border-bottom-color: var(--rule); }

.nav-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand { display: flex; align-items: center; gap: 11px; }
.brand-mark {
  width: 30px; height: 30px;
  flex: 0 0 30px;
  display: grid; place-items: center;
  border-radius: 9px;
  background: var(--acc-tint);
  color: var(--acc);
  font-family: var(--serif);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .02em;
  border: 1px solid color-mix(in srgb, var(--acc) 14%, transparent);
}
.brand-name { font-family: var(--serif); font-size: 16px; font-weight: 600; letter-spacing: .01em; }
.brand-name small { display: block; font-family: var(--mono); font-size: 10px; letter-spacing: .12em; color: var(--ink-3); font-weight: 400; }

.nav-links { display: flex; align-items: center; gap: 4px; }
.nav-links a {
  position: relative;
  padding: 7px 12px;
  border-radius: var(--r-sm);
  font-size: 14px;
  color: var(--ink-2);
  transition: color var(--t), background var(--t);
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 12px; right: 12px; bottom: 2px;
  height: 2px;
  border-radius: 2px;
  background: var(--acc);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--t);
}
.nav-links a:hover { color: var(--ink); }
.nav-links a:hover::after,
.nav-links a.is-active::after { transform: scaleX(1); }
.nav-links a.is-active { color: var(--ink); }

.nav-tools { display: flex; align-items: center; gap: 8px; }
.tool {
  height: 34px;
  min-width: 34px;
  padding: 0 10px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  border: 1px solid var(--rule);
  border-radius: 999px;
  background: var(--surface);
  color: var(--ink-2);
  font-size: 12.5px;
  font-family: var(--mono);
  letter-spacing: .04em;
  transition: border-color var(--t), color var(--t), box-shadow var(--t), transform var(--t);
}
.tool:hover { color: var(--ink); border-color: var(--ink-3); box-shadow: var(--shadow-1); }
.tool:active { transform: translateY(1px); }
.nav-burger { display: none; }

/* ------------------------------------------------------------- 05 Hero */
.hero {
  position: relative;
  padding: 74px 0 0;
  overflow: hidden;
}
/* Whisper-quiet paper grid + one soft accent wash */
.hero::before {
  content: "";
  position: absolute;
  inset: -20% -10% auto -10%;
  height: 130%;
  background:
    radial-gradient(38% 46% at 12% 8%,  color-mix(in srgb, var(--tint-mint) 74%, transparent), transparent 70%),
    radial-gradient(34% 42% at 88% 0%,  color-mix(in srgb, var(--tint-sky) 54%, transparent),  transparent 72%);
  pointer-events: none;
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--rule-2) 1px, transparent 1px),
    linear-gradient(to bottom, var(--rule-2) 1px, transparent 1px);
  background-size: 96px 96px;
  opacity: .5;
  mask-image: radial-gradient(70% 60% at 50% 20%, #000 0%, transparent 78%);
  -webkit-mask-image: radial-gradient(70% 60% at 50% 20%, #000 0%, transparent 78%);
  pointer-events: none;
}
.hero > .wrap { position: relative; z-index: 1; }

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 340px;
  gap: 56px;
  align-items: start;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 6px 14px 6px 11px;
  border: 1px solid var(--rule);
  border-radius: 999px;
  background: var(--surface);
  background: color-mix(in srgb, var(--surface) 80%, transparent);
  font-size: 12.5px;
  color: var(--ink-2);
  letter-spacing: .02em;
}
.eyebrow i {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--deep-mint);
  box-shadow: 0 0 0 3px var(--tint-mint);
}

/* The name is set in one ink; colour belongs to the small Latin line under it,
   so the accent reads as typographic hierarchy rather than emphasis. */
.hero h1 {
  margin-top: 26px;
  font-family: var(--serif);
  font-size: clamp(46px, 7.4vw, 82px);
  font-weight: 600;
  line-height: 1.04;
  letter-spacing: -.02em;
  color: var(--ink);
}
.hero h1 .latin {
  display: block;
  font-size: .5em;
  letter-spacing: -.01em;
  color: var(--acc);
  margin-top: .18em;
  font-weight: 500;
}

.hero-motto {
  margin-top: 22px;
  font-family: var(--serif);
  font-size: clamp(17px, 2.1vw, 21px);
  font-style: italic;
  color: var(--ink);
  padding-left: 18px;
  border-left: 3px solid var(--acc-tint);
}

.hero-lead {
  margin-top: 24px;
  max-width: 620px;
  color: var(--ink-2);
  font-size: 15.5px;
}
.hero-lead b { color: var(--ink); }

.roles { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 26px; }
.role {
  padding: 6px 13px;
  border-radius: 999px;
  font-size: 13px;
  border: 1px solid var(--rule);
  background: var(--surface);
  color: var(--ink-2);
}
.role.is-key { border-color: var(--acc-tint); background: var(--acc-tint); color: var(--acc); }

.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 44px;
  padding: 0 20px;
  border-radius: 999px;
  font-size: 14.5px;
  font-weight: 500;
  border: 1px solid transparent;
  transition: transform var(--t), box-shadow var(--t), background var(--t), border-color var(--t), color var(--t);
}
.btn svg { width: 15px; height: 15px; }
.btn--solid { background: var(--ink); color: var(--paper); }
.btn--solid:hover { transform: translateY(-2px); box-shadow: var(--shadow-2); }
.btn--ghost { border-color: var(--rule); background: var(--surface); color: var(--ink-2); }
.btn--ghost:hover { color: var(--ink); border-color: var(--ink-3); transform: translateY(-2px); }

/* Business-card style aside */
.card-id {
  position: relative;
  border: 1px solid var(--rule);
  border-radius: var(--r-lg);
  background: var(--surface);
  background: color-mix(in srgb, var(--surface) 92%, transparent);
  box-shadow: var(--shadow-2);
  padding: 22px;
  overflow: hidden;
}
.card-id::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: var(--acc);
}
.card-id-head { display: flex; align-items: center; gap: 12px; padding-bottom: 16px; border-bottom: 1px solid var(--rule-2); margin-bottom: 6px; }
.card-id-mark {
  width: 44px; height: 44px; flex: 0 0 44px;
  display: grid; place-items: center;
  border-radius: 12px;
  background: var(--acc-tint);
  font-family: var(--serif);
  font-size: 17px; font-weight: 700;
  color: var(--acc);
  border: 1px solid color-mix(in srgb, var(--acc) 14%, transparent);
}
.card-id-head h2 { font-family: var(--serif); font-size: 18px; font-weight: 600; line-height: 1.3; }
.card-id-head p { font-size: 12px; color: var(--ink-3); font-family: var(--mono); letter-spacing: .04em; }
.card-id-list { display: grid; gap: 2px; }
.card-id-list li {
  display: grid;
  grid-template-columns: 20px 1fr;
  gap: 11px;
  padding: 10px 0;
  font-size: 13.5px;
  color: var(--ink-2);
  border-bottom: 1px dashed var(--rule-2);
}
.card-id-list li:last-child { border-bottom: 0; }
.card-id-list .k { font-size: 14px; line-height: 1.5; }
.card-id-list b { color: var(--ink); }
.card-id-list a { color: var(--deep-sky); border-bottom: 1px solid color-mix(in srgb, var(--deep-sky) 30%, transparent); }

/* Metric strip — the "key numbers" line, set in tabular figures */
.strip {
  position: relative;
  margin-top: 60px;
  border-top: 1px solid var(--rule);
  background: var(--surface);
  background: color-mix(in srgb, var(--surface) 55%, transparent);
}
.strip-grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.metric {
  padding: 26px 22px 30px;
  border-right: 1px solid var(--rule-2);
  position: relative;
}
.metric:last-child { border-right: 0; }
.metric::before {
  content: "";
  position: absolute;
  left: 22px; top: -1px;
  width: 34px; height: 3px;
  border-radius: 0 0 3px 3px;
  background: var(--acc);
  opacity: .8;
}
.metric .num {
  font-family: var(--num);
  font-size: clamp(28px, 3.6vw, 38px);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -.02em;
  font-variant-numeric: tabular-nums lining-nums;
  font-feature-settings: "tnum" 1, "lnum" 1;
}
.metric .num small { font-size: .42em; color: var(--ink-3); font-weight: 500; margin-left: 3px; letter-spacing: 0; font-family: var(--sans); }
.metric .cap { margin-top: 8px; font-size: 12.8px; color: var(--ink-3); line-height: 1.55; }

/* ---------------------------------------------------------- 06 About/Skills */
.about-grid { display: grid; grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr); gap: 52px; align-items: start; }

.facts { display: grid; gap: 12px; }
.fact {
  display: grid;
  grid-template-columns: 34px 1fr;
  gap: 14px;
  padding: 16px 18px;
  border: 1px solid var(--rule);
  border-radius: var(--r-md);
  background: var(--surface);
  box-shadow: var(--shadow-1);
  transition: transform var(--t), box-shadow var(--t), border-color var(--t);
}
.fact:hover { transform: translateY(-2px); box-shadow: var(--shadow-2); border-color: var(--acc-tint); }
.fact .ico {
  width: 34px; height: 34px;
  display: grid; place-items: center;
  border-radius: 9px;
  background: var(--acc-tint);
  font-size: 15px;
}
.fact h3 { font-size: 13px; letter-spacing: .06em; text-transform: uppercase; color: var(--ink-3); font-weight: 600; margin-bottom: 4px; }
.fact p { font-size: 13.8px; color: var(--ink-2); line-height: 1.72; }

.skill-grid {
  margin-top: 54px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--rule-2);
  border: 1px solid var(--rule-2);
  border-radius: var(--r-md);
  overflow: hidden;
}
.skill-col { background: var(--surface); padding: 24px 26px 26px; }
.skill-col h3 {
  display: flex; align-items: baseline; gap: 9px;
  font-size: 13px;
  letter-spacing: .05em;
  text-transform: uppercase;
  color: var(--ink-3);
  font-weight: 600;
  margin-bottom: 16px;
}
.skill-col h3 span.n { font-family: var(--mono); color: var(--acc); font-size: 11px; letter-spacing: .1em; }
.chips { display: flex; flex-wrap: wrap; gap: 7px; }
.chips span {
  padding: 5px 11px;
  border-radius: 999px;
  border: 1px solid var(--rule);
  background: var(--paper);
  font-size: 12.6px;
  color: var(--ink-2);
  transition: border-color var(--t), color var(--t), background var(--t);
}
.chips span:hover { border-color: var(--acc-tint); background: var(--acc-tint); color: var(--acc); }
.chips span.is-em { border-color: var(--acc-tint); color: var(--acc); background: var(--acc-tint); font-weight: 500; }

/* ------------------------------------------------------ 07 Project entries */
.entries { border-top: 1px solid var(--rule); }

.entry {
  position: relative;
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 26px;
  padding: 40px 0 42px;
  border-bottom: 1px solid var(--rule);
  transition: background var(--t);
}
.entry::before {
  content: "";
  position: absolute;
  left: -28px; top: 40px; bottom: 42px;
  width: 2px;
  border-radius: 2px;
  background: var(--acc);
  opacity: .3;
  transition: opacity var(--t);
}
.entry:hover::before { opacity: .95; }

.entry-rank { text-align: left; }
.entry-rank .n {
  font-family: var(--num);
  font-size: 38px;
  font-weight: 600;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--ink);
  display: block;
  font-variant-numeric: tabular-nums lining-nums;
  font-feature-settings: "tnum" 1, "lnum" 1;
}
.entry-rank .k {
  display: block;
  margin-top: 9px;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--ink-3);
}
.entry-rank .flag {
  display: inline-block;
  margin-top: 12px;
  padding: 3px 9px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--acc);
  background: var(--acc-tint);
  border: 1px solid color-mix(in srgb, var(--acc) 22%, transparent);
  white-space: nowrap;
}

.entry h3 {
  font-family: var(--serif);
  font-size: clamp(20px, 2.4vw, 25px);
  font-weight: 600;
  line-height: 1.35;
  letter-spacing: -.008em;
}
.entry .sub {
  margin-top: 7px;
  font-size: 13.4px;
  color: var(--ink-3);
  font-family: var(--mono);
  letter-spacing: .02em;
}
.entry .meta {
  margin-top: 14px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 10px;
  font-size: 13.2px;
  color: var(--ink-2);
}
.entry .meta .sep { color: var(--rule); }
.entry .meta em {
  font-style: normal;
  padding: 3px 9px;
  border-radius: 999px;
  border: 1px solid var(--rule);
  background: var(--paper);
  color: var(--ink-2);
  font-size: 12px;
}
.entry .desc { margin-top: 15px; font-size: 15px; color: var(--ink-2); max-width: 780px; }
.entry .desc strong { color: var(--ink); }

/* Headline numbers, three across — the scan line for a hiring reader */
.stats {
  margin-top: 20px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  background: var(--rule-2);
  border: 1px solid var(--rule-2);
  border-radius: var(--r-md);
  overflow: hidden;
}
.stat { background: var(--paper); padding: 13px 15px 14px; }
.stat b {
  display: block;
  font-family: var(--num);
  font-size: 20px;
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -.01em;
  color: var(--ink);
  font-variant-numeric: tabular-nums lining-nums;
  font-feature-settings: "tnum" 1, "lnum" 1;
}
.stat span { display: block; margin-top: 4px; font-size: 12.2px; color: var(--ink-3); line-height: 1.6; }

.entry-foot {
  margin-top: 20px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.tags { display: flex; flex-wrap: wrap; gap: 6px; }
.tags span {
  font-family: var(--mono);
  font-size: 11.4px;
  letter-spacing: .03em;
  padding: 4px 9px;
  border-radius: 5px;
  background: var(--paper-2);
  color: var(--ink-3);
  border: 1px solid var(--rule-2);
}
.link-out {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-size: 13.5px;
  font-weight: 500;
  color: var(--acc);
  border-bottom: 1px solid color-mix(in srgb, var(--acc) 32%, transparent);
  padding-bottom: 2px;
  transition: gap var(--t), border-color var(--t);
}
.link-out:hover { gap: 11px; border-bottom-color: var(--acc); }
.link-out svg { width: 14px; height: 14px; }
.link-off {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-size: 12.8px;
  color: var(--ink-3);
  padding: 4px 10px;
  border: 1px dashed var(--rule);
  border-radius: 999px;
}

/* ------------------- Evidence figures: numbers drawn from the result tables */
.fig {
  margin-top: 22px;
  padding: 16px 18px 14px;
  border: 1px solid var(--rule-2);
  border-radius: var(--r-md);
  background: var(--surface);
  max-width: 780px;
}
.fig figcaption {
  font-size: 12.6px;
  color: var(--ink-3);
  line-height: 1.7;
  margin-bottom: 14px;
}
.fig figcaption b {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--ink-2);
  margin-right: 6px;
}

/* Horizontal bars. Widths are inline (they are the data); colour is the token. */
.bars { display: grid; gap: 11px; }
.bars li {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 1.25fr) 62px;
  align-items: center;
  gap: 14px;
}
.bars .lb { font-size: 12.6px; color: var(--ink-2); line-height: 1.5; min-width: 0; }
.bars .lb em {
  display: block;
  font-style: normal;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-3);
  letter-spacing: .02em;
  margin-top: 1px;
}
.bars .track {
  height: 12px;
  border-radius: 3px;
  background: var(--paper-2);
  box-shadow: inset 0 0 0 1px var(--rule-2);
  overflow: hidden;
}
.bars .track i {
  display: block;
  height: 100%;
  min-width: 3px;
  border-radius: 3px;
  background: var(--acc);
  opacity: .42;
  transition: opacity var(--t);
}
.bars li:hover .track i { opacity: .8; }
.bars li.is-final .track i { opacity: 1; }
.bars .vl {
  font-family: var(--mono);
  font-size: 12.4px;
  color: var(--ink-2);
  text-align: right;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}
.bars li.is-final .vl { color: var(--acc); font-weight: 600; }

/* Interval / density plot on a computed scale (0 % at 50% of the track) */
.box {
  position: relative;
  height: 74px;
  margin: 4px 0 6px;
  border-radius: 3px;
  background:
    repeating-linear-gradient(to right, var(--rule-2) 0 1px, transparent 1px 10%);
  background-size: 100% 100%;
}
.box .spread {
  position: absolute;
  top: 24px;
  height: 26px;
  border-radius: 4px;
  background: var(--acc-tint);
  border: 1px solid color-mix(in srgb, var(--acc) 22%, transparent);
}
.box .m,
.box .z,
.box .w { position: absolute; top: 18px; width: 0; }
.box .m i, .box .z i, .box .w i {
  display: block;
  width: 2px;
  height: 38px;
  margin-left: -1px;
  border-radius: 2px;
  background: var(--acc);
  opacity: .85;
}
.box .z i { background: var(--ink-3); opacity: .5; height: 28px; margin-top: 5px; }
.box .w i { height: 26px; margin-top: 6px; opacity: .55; }
.box em {
  position: absolute;
  top: 42px;
  left: 0;
  transform: translateX(-50%);
  font-style: normal;
  font-family: var(--mono);
  font-size: 10.6px;
  color: var(--ink-3);
  white-space: nowrap;
}

/* Formula chips: the statistical content of a claim, in typeset form */
.fmls { display: grid; gap: 8px; margin-bottom: 4px; }
.fml {
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--paper);
  border: 1px solid var(--rule-2);
  border-radius: var(--r-sm);
  padding: 9px 13px;
}
.fml em {
  font-style: normal;
  font-family: var(--sans);
  font-size: 11.6px;
  color: var(--ink-3);
  letter-spacing: .01em;
}

/* Funnel: bar lengths proportional to sessions */
.funnel { display: grid; gap: 9px; }
.funnel li {
  display: grid;
  grid-template-columns: 78px minmax(0, 1fr) 74px 60px;
  align-items: center;
  gap: 12px;
}
.funnel .fs { font-size: 12.7px; color: var(--ink-2); }
.funnel li.hot .fs { color: var(--ink); font-weight: 600; }
.funnel .fw { border-bottom: 1px solid var(--rule-2); padding-bottom: 3px; }
.funnel .fw i {
  display: block;
  height: 18px;
  min-width: 4px;
  border-radius: 4px;
  background: var(--acc);
  opacity: .38;
}
.funnel li.hot .fw i { opacity: 1; }
.funnel .fv {
  font-family: var(--mono);
  font-size: 12.2px;
  color: var(--ink);
  text-align: right;
  font-variant-numeric: tabular-nums;
}
.funnel .fr {
  font-family: var(--mono);
  font-size: 11.4px;
  color: var(--ink-3);
  text-align: right;
  font-variant-numeric: tabular-nums;
}
.funnel .fr.hot,
.funnel li.hot .fr { color: var(--acc); font-weight: 600; }

.fig-note { margin-top: 12px; font-size: 12.3px; color: var(--ink-3); line-height: 1.75; }
.fig-note b { color: var(--ink-2); }

/* Rendered figures: PNGs produced by tools/make_figures.py from the repo results.
   Same caption grammar as the hand-drawn figures above, so the two read as one set. */
.media {
  margin-top: 24px;
  padding: 16px 18px 14px;
  border: 1px solid var(--rule-2);
  border-radius: var(--r-md);
  background: var(--surface);
  max-width: 780px;
}
.media figcaption {
  font-size: 12.6px;
  color: var(--ink-3);
  line-height: 1.7;
  margin-bottom: 12px;
}
.media figcaption b {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--ink-2);
  margin-right: 6px;
}
.media-btn {
  display: block;
  width: 100%;
  padding: 0;
  border: 1px solid var(--rule-2);
  border-radius: var(--r-sm);
  background: var(--paper);
  overflow: hidden;
  cursor: zoom-in;
  transition: border-color var(--t), box-shadow var(--t);
}
.media-btn:hover { border-color: var(--acc-tint); box-shadow: var(--shadow-1); }
.media-btn:focus-visible { outline: 2px solid var(--deep-sky); outline-offset: 2px; }
.media-btn img { width: 100%; height: auto; }
.media-note { margin-top: 12px; font-size: 12.3px; color: var(--ink-3); line-height: 1.75; }
.media-note b { color: var(--ink-2); }

/* Full-size viewer */
.viewer {
  width: min(96vw, 1400px);
  max-width: none;
  max-height: 94vh;
  padding: 0;
  border: 1px solid var(--rule);
  border-radius: var(--r-lg);
  background: var(--surface);
  color: var(--ink);
  box-shadow: var(--shadow-3);
  overflow: hidden;
}
.viewer::backdrop { background: rgba(18, 24, 29, .62); backdrop-filter: blur(2px); }
.viewer-bar {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 14px;
  padding: 12px 14px 11px 16px;
  border-bottom: 1px solid var(--rule-2);
}
.viewer-cap { font-size: 12.6px; color: var(--ink-3); line-height: 1.6; }
.viewer-x {
  flex: 0 0 auto;
  width: 30px; height: 30px;
  display: grid; place-items: center;
  border-radius: 50%;
  border: 1px solid var(--rule);
  color: var(--ink-2);
  font-size: 13px;
  transition: color var(--t), border-color var(--t);
}
.viewer-x:hover { color: var(--ink); border-color: var(--ink-3); }
.viewer-img {
  display: block;
  width: 100%;
  max-height: calc(94vh - 56px);
  object-fit: contain;
  background: var(--paper);
}

/* Footnote-ish line under the entries */
.note {
  margin-top: 32px;
  font-size: 13.6px;
  color: var(--ink-3);
  padding-left: 16px;
  border-left: 2px solid var(--acc-tint);
  max-width: 860px;
}
.note a { color: var(--deep-sky); border-bottom: 1px solid color-mix(in srgb, var(--deep-sky) 30%, transparent); }
.note a:hover { color: var(--ink); }

/* ----------------------------------------------------------- 08 Honors */
.honor-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1px; background: var(--rule-2); border: 1px solid var(--rule-2); border-radius: var(--r-md); overflow: hidden; }
.honor { background: var(--surface); padding: 26px 28px 28px; }
.honor h3 {
  display: flex; align-items: center; gap: 10px;
  font-size: 13px; letter-spacing: .05em; text-transform: uppercase;
  color: var(--ink-3); font-weight: 600; margin-bottom: 16px;
}
.honor h3::after { content: ""; flex: 1; height: 1px; background: var(--rule-2); }
.honor h3 .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--acc); flex: 0 0 8px; }
.honor ul { display: grid; gap: 11px; }
.honor li {
  display: grid;
  grid-template-columns: 74px minmax(0, 1fr);
  gap: 12px;
  font-size: 14px;
  color: var(--ink-2);
  align-items: baseline;
}
.honor li .yr {
  font-family: var(--mono);
  font-size: 11.5px;
  color: var(--ink-3);
  letter-spacing: .02em;
  padding-top: 2px;
  font-variant-numeric: tabular-nums;
}
.honor li b { color: var(--ink); }

/* --------------------------------------------------- 09 Contact / footer */
.connect { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.connect a {
  display: block;
  padding: 26px 24px;
  border: 1px solid var(--rule);
  border-radius: var(--r-lg);
  background: var(--surface);
  box-shadow: var(--shadow-1);
  transition: transform var(--t), box-shadow var(--t), border-color var(--t);
}
.connect a:hover { transform: translateY(-3px); box-shadow: var(--shadow-3); border-color: var(--acc-tint); }
.connect .ico {
  width: 38px; height: 38px;
  display: grid; place-items: center;
  border-radius: 11px;
  background: var(--acc-tint);
  font-size: 16px;
  margin-bottom: 16px;
}
.connect .lb { display: block; font-family: var(--mono); font-size: 11px; letter-spacing: .14em; text-transform: uppercase; color: var(--ink-3); }
.connect .vl { display: block; margin-top: 6px; font-size: 15px; color: var(--ink); font-weight: 500; word-break: break-all; }

.footer { border-top: 1px solid var(--rule); padding: 36px 0 48px; background: var(--paper-2); }
.footer-inner { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 18px; font-size: 13px; color: var(--ink-3); }
.footer-inner a { color: var(--ink-2); border-bottom: 1px solid var(--rule); }
.footer-inner a:hover { color: var(--ink); }

.to-top {
  position: fixed;
  right: 24px; bottom: 24px;
  width: 42px; height: 42px;
  display: grid; place-items: center;
  border-radius: 50%;
  background: var(--surface);
  border: 1px solid var(--rule);
  box-shadow: var(--shadow-2);
  color: var(--ink-2);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity var(--t), transform var(--t), visibility var(--t), color var(--t);
  z-index: 90;
}
.to-top.is-on { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { color: var(--acc); }

/* ------------------------------------------------ 10 Projects page extras */
.page-head { padding: 60px 0 0; }
.page-head h1 {
  font-family: var(--serif);
  font-size: clamp(34px, 5vw, 52px);
  font-weight: 600;
  letter-spacing: -.02em;
  line-height: 1.12;
}
.page-head .lead { margin-top: 18px; max-width: 700px; color: var(--ink-2); font-size: 16px; }

.crumb {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: var(--mono); font-size: 11.5px; letter-spacing: .1em;
  text-transform: uppercase; color: var(--ink-3);
  margin-bottom: 20px;
}
.crumb a:hover { color: var(--acc); }

/* Booktabs-style table (三线表) — the scoring surface of the whole site */
.figure { margin-top: 32px; }
.table-scroll {
  overflow-x: auto;
  border-radius: var(--r-sm);
  /* A hairline under the scrollable region hints that the table can move. */
  border-bottom: 1px solid var(--rule-2);
  scrollbar-width: thin;
}
.table-scroll::-webkit-scrollbar { height: 6px; }
.table-scroll::-webkit-scrollbar-thumb { background: var(--rule); border-radius: 3px; }
table.booktabs { min-width: 720px; font-size: 14px; }
table.booktabs caption {
  caption-side: top;
  text-align: left;
  font-size: 13px;
  color: var(--ink-3);
  padding-bottom: 12px;
  line-height: 1.7;
}
table.booktabs caption b { color: var(--ink-2); font-weight: 600; }
table.booktabs thead th {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--ink-3);
  font-weight: 600;
  text-align: left;
  padding: 12px 14px;
  border-top: 1.6px solid var(--ink);
  border-bottom: 1px solid var(--rule);
  white-space: nowrap;
}
table.booktabs tbody td {
  padding: 14px;
  border-bottom: 1px solid var(--rule-2);
  color: var(--ink-2);
  vertical-align: top;
}
table.booktabs tbody tr:last-child td { border-bottom: 1.6px solid var(--ink); }
table.booktabs tbody tr:hover td { background: var(--paper-2); }
table.booktabs .num,
table.booktabs .rk,
table.booktabs .wl {
  font-family: var(--mono);
  font-size: 13px;
  text-align: center;
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}
table.booktabs .rk { font-family: var(--num); font-size: 17px; font-weight: 600; color: var(--ink); }
table.booktabs .wl { color: var(--ink); font-weight: 600; }
table.booktabs .strong-row td { background: color-mix(in srgb, var(--acc-tint) 32%, transparent); }
table.booktabs .strong-row:hover td { background: color-mix(in srgb, var(--acc-tint) 62%, transparent); }
table.booktabs td.name { color: var(--ink); font-weight: 550; }
table.booktabs td.name small { display: block; font-weight: 400; color: var(--ink-3); font-size: 12.4px; margin-top: 3px; font-family: var(--mono); }
table.booktabs td.name small.name-flag {
  display: inline-block;
  margin: 0 0 0 7px;
  padding: 1px 7px;
  border-radius: 999px;
  font-size: 11px;
  letter-spacing: .01em;
  color: var(--acc);
  background: var(--acc-tint);
  border: 1px solid color-mix(in srgb, var(--acc) 20%, transparent);
  vertical-align: 1px;
}
table.booktabs .tbl-off { color: var(--ink-3); font-size: 13px; }
table.booktabs .tbl-off .zh,
table.booktabs .tbl-off .en { border-bottom: 0; }
table.booktabs a { color: var(--deep-sky); border-bottom: 1px solid color-mix(in srgb, var(--deep-sky) 28%, transparent); }
table.booktabs a:hover { border-bottom-color: var(--deep-sky); }

.table-note { margin-top: 18px; font-size: 12.8px; color: var(--ink-3); line-height: 1.8; max-width: 980px; }
.table-note b { color: var(--ink-2); }
.table-note.reveal { margin-top: 34px; }

/* Compact project cards on the full-list page */
.cards { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; margin-top: 32px; }
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 24px 24px 22px;
  border: 1px solid var(--rule);
  border-radius: var(--r-lg);
  background: var(--surface);
  box-shadow: var(--shadow-1);
  overflow: hidden;
  transition: transform var(--t), box-shadow var(--t), border-color var(--t);
}
.card::before {
  content: "";
  position: absolute; inset: 0 0 auto 0; height: 3px;
  background: var(--acc);
  opacity: .5;
  transition: opacity var(--t);
}
.card:hover { transform: translateY(-3px); box-shadow: var(--shadow-3); border-color: var(--acc-tint); }
.card:hover::before { opacity: 1; }
.card-top { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.card-rk { font-family: var(--mono); font-size: 11.5px; letter-spacing: .1em; color: var(--acc); font-weight: 600; }
.card-kind {
  font-size: 11px; padding: 3px 9px; border-radius: 999px;
  background: var(--acc-tint); color: var(--acc); font-weight: 600;
}
.card h3 { font-family: var(--serif); font-size: 18.5px; font-weight: 600; line-height: 1.42; }
.card .cs { margin-top: 6px; font-size: 12.4px; font-family: var(--mono); color: var(--ink-3); }
.card p.body { margin-top: 14px; font-size: 14px; color: var(--ink-2); flex: 1; }
.card .kpis { margin-top: 16px; display: grid; gap: 7px; }
.card .kpis li { font-size: 13px; color: var(--ink-2); display: grid; grid-template-columns: 12px 1fr; gap: 9px; }
.card .kpis li::before { content: ""; width: 5px; height: 5px; margin-top: .6em; border-radius: 50%; background: var(--acc); opacity: .65; }
.card .kpis b { font-family: var(--mono); color: var(--ink); font-size: .96em; }
.card .card-foot {
  margin-top: 18px; padding-top: 14px; border-top: 1px dashed var(--rule-2);
  display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap;
}

/* generic two-column blocks on inner page */
.split { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 40px; }
.panel {
  border: 1px solid var(--rule);
  border-radius: var(--r-lg);
  background: var(--surface);
  padding: 26px 28px;
  box-shadow: var(--shadow-1);
}
.panel h3 { font-family: var(--serif); font-size: 18px; font-weight: 600; margin-bottom: 12px; }
.panel p { font-size: 14.4px; color: var(--ink-2); }
.panel p + p { margin-top: 10px; }
.panel ul.tick { margin-top: 14px; display: grid; gap: 9px; }
.panel ul.tick li { font-size: 14px; color: var(--ink-2); display: grid; grid-template-columns: 16px 1fr; gap: 10px; }
.panel ul.tick li::before { content: "→"; color: var(--acc); font-size: 13px; line-height: 1.6; }

/* ------------------------------------------------- 11 Motion / responsive */
.reveal { opacity: 0; transform: translateY(14px); transition: opacity .6s var(--ease), transform .6s var(--ease); }
.reveal.is-in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .001ms !important; transition-duration: .001ms !important; }
  .reveal { opacity: 1; transform: none; }
}

@media (max-width: 1024px) {
  .hero-grid { grid-template-columns: minmax(0, 1fr); gap: 40px; }
  .card-id { max-width: 520px; }
  .about-grid { grid-template-columns: minmax(0, 1fr); gap: 36px; }
  .connect { grid-template-columns: repeat(2, 1fr); }
  .skill-grid, .honor-grid, .cards { grid-template-columns: minmax(0, 1fr); }
  .split { grid-template-columns: minmax(0, 1fr); gap: 20px; }
}

@media (max-width: 860px) {
  .nav-links {
    position: absolute;
    top: var(--nav-h); left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 12px 20px 18px;
    background: var(--paper);
    border-bottom: 1px solid var(--rule);
    box-shadow: var(--shadow-2);
    display: none;
  }
  .nav-links.is-open { display: flex; }
  .nav-links a { padding: 11px 12px; }
  .nav-links a::after { display: none; }
  .nav-burger { display: inline-flex; }
}

@media (max-width: 760px) {
  .wrap { padding-inline: 20px; }
  .section { padding: 62px 0; }
  .hero { padding-top: 50px; }
  .strip-grid { grid-template-columns: repeat(2, 1fr); }
  .metric:nth-child(2) { border-right: 0; }
  .metric:nth-child(-n+2) { border-bottom: 1px solid var(--rule-2); }
  .entry { grid-template-columns: minmax(0, 1fr); gap: 14px; padding: 32px 0 34px; }
  .entry::before { left: -12px; top: 32px; bottom: 34px; }
  .entry-rank { display: flex; align-items: baseline; gap: 12px; flex-wrap: wrap; }
  .entry-rank .n { font-size: 30px; }
  .entry-rank .k { margin-top: 0; }
  .entry-rank .flag { margin-top: 0; }
  .connect { grid-template-columns: minmax(0, 1fr); }
  .honor li { grid-template-columns: 62px minmax(0, 1fr); }
  .stats { grid-template-columns: minmax(0, 1fr); }
  .bars li { grid-template-columns: minmax(0, 1fr) 58px; row-gap: 6px; }
  .bars .lb { grid-column: 1 / -1; }
  .bars .track { grid-column: 1; }
  .funnel li { grid-template-columns: 72px minmax(0, 1fr); row-gap: 3px; gap: 10px; }
  .funnel .fs { grid-column: 1; grid-row: 1 / span 2; align-self: center; }
  .funnel .fw { grid-column: 2; grid-row: 1; }
  .funnel .fv { grid-column: 2; grid-row: 2; text-align: left; font-size: 11.6px; }
  .funnel .fr { grid-column: 2; grid-row: 2; text-align: right; font-size: 11px; }
  .fig { padding: 14px 14px 12px; }
}

/* ------------------------------------------------------------------ Print */
@media print {
  .nav, .to-top, .progress, .hero::before, .hero::after, .hero-cta { display: none !important; }
  body { background: #fff; color: #000; font-size: 11pt; }
  .section { padding: 18pt 0; }
  .section--band, .footer { background: #fff; border-color: #ccc; }
  .entry, .card, .fact, .honor, .connect a { break-inside: avoid; box-shadow: none; }
  .fig, .stats { break-inside: avoid; box-shadow: none; }
  .bars .track i, .funnel .fw i, .box .spread { -webkit-print-color-adjust: exact; print-color-adjust: exact; }
  .reveal { opacity: 1 !important; transform: none !important; }
  a[href^="http"]::after { content: " (" attr(href) ")"; font-size: 9pt; color: #666; }
  html[data-lang="zh"] .en, html[data-lang="en"] .zh { display: none !important; }
}